An irrigation controller is a device used to control electrically or otherwise operated valves which control the flow of water to sprinkler heads and driplines in an irrigation system. A single irrigation valve typically controls the flow of water to a specific area of a landscape. Such specific areas are commonly referred to as stations or zones.
The control of water applied to each zone allows for more efficient use of the available water supply by providing a manner whereby differential amounts of water may be applied according to the particular needs of dissimilar areas of the landscape. Also, this division of the landscape to be irrigated into a number of zones enables each zone to receive an appropriate amount of water at a pressure sufficient for the proper operation of the sprinkler heads within that zone, and is often necessary due to limitations in the capacity of the water being supplied to the system as well as the size of the piping used to efficiently carry water through the installation.
In recent years, a variety of sophisticated features have been incorporated into residential irrigation controllers. When properly utilized some of these features can contribute to an irrigation system that makes more efficient use of the available water resource. One of the challenges facing those involved in the design, manufacture and marketing of irrigation controllers is to incorporate these important features in a manner that encourages their actual use by the homeowner.
However, even with these efforts, homeowners are often intimidated by the complexity of these devices and the number of variables that make up an irrigation schedule. And beyond the homeowner, the contractors who install, repair, and in some cases maintain irrigation systems, are also confronted with the more advanced and complex array of scheduling choices provided for by some of these devices.
Therefore, while currently available irrigation controllers provide much flexibility in regards to scheduling and fine-tuning of watering activities, these sophisticated controllers also add significant complexity to the task of managing a residential irrigation system. Ease of use, be it in regards to programming an efficient watering schedule, reviewing the settings that make up an existing program, or manually initiating a watering cycle or activating a single zone, has become more important than ever in this type of device.
One manner of addressing the increasing number of parameters associated with the creation of an efficient watering schedule is to provide the user with a visual representation of the various elements which make up an irrigation Program, or Schedule. For example, several existing devices rely upon a rotary dial or switch which can be positioned to point to any one of these elements, such as pointing to a particular zone number or day of the week. However, it can be quite cumbersome to program a device (or to review an existing program) using this strategy since the mechanical dial must be repeatedly repositioned in order to address each of the particular elements which combine to create the irrigation schedule. A related problem found in controllers utilizing this strategy is that they typically have relatively small displays which at any one time provides information pertaining only to the specific parameter currently being edited or reviewed.
For example, with some of these controllers, the only way to identify the zones which have been included in a given watering Program is by rotating the dial through each zone position in order to determine if any run time has been applied to each particular zone. In the case of multi-program controllers capable of managing a number of independent watering schedules this task may be multiplied by the number of available programs.
Some devices geared to the residential user rely upon slider type switches to set the amount of run time for each zone. While this makes it relatively easy to review how long each zone will be activated, these devices often provide a fixed number of discrete selectable run times. Therefore, if a zone requires an amount of run time between two positions on the fixed scale, the user will likely select the higher value, resulting in a greater amount of water being applied than is actually needed for that particular zone. In addition, accurately setting the longer run times required for drip type applications may prove difficult (and in some cases not possible) on a device utilizing this strategy.
In some cases it may become necessary to increase the number of zones within the irrigation system. One example of this would be the need to accommodate a greater number of zones due to modifications made to the original installation. Controllers are often sold with the hardware required to operate a designated (first number) of zones, for example a four station controller may accommodate/operate up to four individual zones. If for any reason there is a need to operate more than the first number of zones for which the existing controller is capable, it may become necessary to replace it with a completely new controller having a greater zone capacity. This can be a time consuming and relatively expensive process.
Some existing controllers provide a manner of increasing the number of zones they are capable of operating by purchasing and installing what are generally referred to as expansion modules. However, controllers using this expansion method must provide additional space within the housing to accommodate these modules than would otherwise be necessary. This leads to products which must be designed to be large enough to accommodate the full number of modules for which they are capable of receiving, regardless of the actual number of modules being utilized in any given installation. Further, improper installation of a module may cause it to become damaged, prevent it from operating properly, or lead to other electrical problems.
Yet another problem with existing irrigation controllers is that they typically are factory set with a designated group of features that may not be modified. For example, a 2 Program capable controller cannot later be upgraded to accommodate 3 Programs. In a closely related situation, the designated set of features cannot be modified regardless of whether or not they are required for a particular installation.
For example, presenting the user with 4 possible start times when no more than 2 will be utilized, or providing advanced features that are not required to meet the scheduling requirements of the particular installation, add undue complexity to the programming process. This increased complexity is often confusing to owners of irrigation systems. Also, the user/homeowner can end up paying for features that he or she doesn't need.
In a related problem, some features of an irrigation schedule are better left to be set by a contractor. If the contractor sets parameters related to these features, and if subsequently an end user resets some of these parameters, the irrigation schedule will typically become inadequate. Often, the contractor will need to reset these parameters to their appropriate values.
Large numbers of irrigation controllers are sold through retail channels such as large hardware box type stores. Generally there is no opportunity for the consumer to evaluate one of these products prior to purchasing it and the consumer is then left with a difficult choice to make in buying an untested product.
Against this background, there exists a need in the industry to provide a novel irrigation controller.